Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The description adds meaningful behavioral context beyond the annotations: 404 means invalid code, not a lookup failure, and metadata varies by kind with concrete examples. This disclosure helps the agent interpret responses correctly and avoid useless retries.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is tightly organized: purpose first, then when to use, then failure semantics, then metadata variation. Every sentence adds distinct value with no redundancy or filler.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

For a simple lookup tool with an output schema, the description covers the key operational details: use case, failure mode, retry guidance, and kind-dependent metadata. Nothing needed for correct invocation is missing.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

The input schema already covers all parameters clearly with 100% schema description coverage, including examples and validation constraints. The description adds useful context about metadata behavior, but does not need to repeat parameter details; baseline 3 is appropriate.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

The description states a precise operation: resolve one code of one classification when both are known. It clearly distinguishes this from broader searching by emphasizing the single-code, confirmatory nature.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description gives a clear use case: confirm a code before putting it on a document to avoid rejected issuance. It also explains that a 404 means the code is wrong and should not be retried, though it does not explicitly name sibling alternatives like search_fiscal_codes.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.